Four PHP text functions strstr strrchr substr stristr

//strstr function
$email = 'liruxing1715@sina.com@qq.com';
$domain = strstr($email, '@');
echo "strstr test result ：{$domain}";
$domain = strstr($email, '@', true);
echo "strstr Test result: {$domain}";
/ *
The test results are:
strstr Test results: @sina.com@qq.com
strstr Test results: liruxing1715
*/
?>

Note: If the string you want to find does not exist If found, then return FALSE. 2. stristr stristr — The function is the same as the strstr function, the only difference is that the case is ambiguous.

3. strrchr strrchr — Displays the last string found, the string to be found, and the subsequent strings.

//strrchr function
$email = 'liruxing1715@sina.com@qq.com';
$domain = strrchr($email, '@');
echo "strrchr test Result: {$domain}";
/*
The test result is:
strrchr Test result: @qq.com
*/
?>

Note: If The string to be searched for is not found, then FALSE is returned. 4. substr substr — In a string, truncate characters according to the given length. Format: string substr ( string $string , int $start [, int $length ] ) Parameter introduction: $string: the string to be intercepted; $start: The starting position to be intercepted, starting from 0 by default; if start is a negative number, the returned string will start from the $start character forward from the end of $string; if the length of string is less than or equal to start, will return FALSE. $length: The end position of interception. If $length is empty, then return from the starting position to the end.

//substr function
$email = 'liruxing1715@sina.com@qq.com';
$domain = substr($email, 10);
echo "substr test results: {$domain}";
$domain = substr($email, 10, 5);
echo "substr Test result: {$domain}";
$domain = substr ($email, -5, 5); //The last digit of the string is -1
echo "substr test result: {$domain}";
/*
The test result is:
substr Test result: 15@sina.com@qq.com
substr Test result: 15@si
substr Test result: q.com
*/
?>